CERN Accelerating science

\noindent Two-particle angular correlations allow the study of hadronization mechanisms. During this process, hadrons are formed from quarks and gluons. The hadronization process is still not fully understood. One of the many theoretical models proposed to describe it is the Lund string model. It is used in the Monte Carlo generator PYTHIA. The angular correlations are a function of two variables: the difference in pseudorapidity $\Delta \eta = \eta_1 - \eta_2$ and the difference in azimuthal angle $\Delta \varphi = \varphi_1 - \varphi_2$. These correlations are sensitive to different hadronization mechanisms. The goal of angular correlation analyses is to understand the mechanism of particle formation by decomposing the particles and understanding the contributions from different sources. For all baryon-baryon and antibaryon-antibaryon pairs studied so far, an anticorrelation is obtained in the vicinity of $\Delta \eta \Delta \varphi = (0,0)$, while a characteristic peak is typically obtained for mesons. Analysis of the angular correlations of $p-\Phi$ could make it possible to answer the question of whether the anticorrelation obtained for all the baryon-baryon and antibaryon-antibaryon pairs studied so far in the vicinity of $\Delta \eta \Delta \varphi = (0,0)$ is an effect influenced by mass. The previously mentioned anticorrelation is not predicted by any of the theoretical models, which means that they do not account for all the effects taking place in this process. Analysis of the $p-\Phi$ system would give theoretical physicists an additional measurement to improve the models used. The main objective of the engineering work is to develop a module for the new $O^2$ software used in the ALICE experiment at CERN, which will allow to obtain the angular correlation function of protons with mesons $\Phi$ in pp collisions. The introduction of the new framework was necessary due to the change of the data acquisition mode in the experiment during Run 3. The AliFemto code used in the previous AliROOT/AliPhysics software can no longer be used, due to significant changes in the format of the data and the form of analysis performed in the $O^2$ framework. In order to do this work, I had to write an analysis tool from scratch. The whole work could be divided into two main parts. The first was to develop the software so that $O^2$ mesons could be reconstructed. This was a purely engineering part and the practical part had to be finalized before I could start working on the second part, namely studying the correlation of identified hadrons with $\Phi$ mesons.